Feeding Habits

Taxonomie

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Humpback whales are renowned for their charismatic, awe-inspiring behaviours above and below the ocean’s surface. Humpbacks frequently launch themselves into the air and land with a splash, known as breaching. They also slap the surface of the water with their long, jagged pectoral fins, the largest relative to body size of any whale. Their equally huge flukes are uniquely marked with mottled patterns like fingerprints, which scientists use to identify individuals using photo-identification catalogues. Humpbacks can also be tracked acoustically, as they sing the most complex songs of any marine mammal and can be heard from hundreds of kilometers away. These songs are often repeated for hours by males to attract females, and can change over time as whales learn new dialogues from each other. Their incredible social behaviours don’t stop there: humpback pods will feed together by encircling a school of small fish with bubbles, condensing them in a so-called ‘bubble net’ for easy capture with a single lunge.

Humpback whales are slow swimmers and spend much of their time near the surface: this previously made them an easy target for overexploitation by commercial whaling. While their populations have rebounded dramatically, they are still well below their pre-whaling estimates. This is because of modern threats to their survival, including heavy harvest of their prey by commercial fisheries, particularly small fish like capelin, herring, or sand lance. Reduced prey availability impedes their prolonged growth and survival.

Another serious threat to humpback whales is interactions with fishing vessels. Humpback whales are the most commonly reported species involved in vessel strikes as shipping and fishing activities often overlap with key breeding and feeding areas. Shipping can exclude whales from important habitat, and underwater noise from engines, propellers and other moving parts on a ship can mask their vocal communications.

Humpback whales are also at risk of entanglement in fishing gear, which can interfere with their normal movement and feeding, potentially suffocating or starving them. The catch of non-target fish and ocean wildlife, or “bycatch,” results in unnecessary waste and harm to many marine species, including humpback whales. Oceana Canada is working to reduce bycatch and better protect species at risk. Find out more about how you can help at Oceana.ca/Bycatch.